Depomed says shingles pain drug meets study goal

MENLO PARK, Calif. 
Depomed Inc. on Monday reported a successful late stage clinical trial of a drug intended to treat pain following the viral infection shingles, and its shares soared on the news.

The company said its DM-1796 significantly reduced post-shingles pain compared to placebo after 10 weeks of treatment. Depomed said it plans to file for Food and Drug Administration approval by the end of March 2010, and in morning trading, its shares surged to a three-year high.

Early in the session, Depomed shares advanced $1.35, or 30.6 percent, to $5.76, and they peaked at $6.21, their highest price since June 2006. More than 2 million shares changed hands by 10 a.m. About 288,000 shares trade on an average full day.

DM-1796 is an extended-release form of gabapentin, which is used to treat pain disorders and epilepsy. Depomed said its drug needs to be taken only once per day, compared with other versions that have to be used four or five times a day, and the company said DM-1796 may have fewer side effects due to its lower dosing.

Depomed is studying the drug in doses of 300 milligrams and 600 milligrams per day, but in the trial, patients were given 1800 milligrams per day. The most common side effects were dizziness and tiredness. A total of 452 patients were enrolled in the study.

Solvay Pharmaceuticals has the license rights to DM-1796 in the U.S., Canada and Mexico as a pain treatment. That business is being bought by Abbott Laboratories for $7.6 billion.

Also jumping in early trading were shares of Xenoport Inc., which is also developing a gabapentin-based drug as a treatment for pain following shingles. Xenoport and its partner, GlaxoSmithKline, reported positive results from a mid stage trial in September.